Stihl 029 to 039 - 49mm Piston Build - Starter Issue! (No Decomp)

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B.C.

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Rebuilt an 029 using a nice meteor 49mm P&C kit that went together nicely. Seal area was a bit odd and different from the original but no issues there, passed pressure test after assembly with flying colors.

I didn't use the decomp, wanted to keep that off to eliminate any possibility of it coming apart and ruining the piston in the future. (Have a decomp on order, would kind of rather not use it if I don't have to)

Problem is I can't hardly pull it over! Its like I can get one revolution of the motor, and it just binds hard. Both starters work just fine on my 290. Take the plug out and it pulls over just fine, no issues, smooth as butter. Seems like it has so much compression that the starter just can't lug it and it's wanting to bust the darn pawl off. Do they make a starter with 2 pawls? Any ideas?

Checked the plug, no slappin there, Bosch WSR6F. Also removed clutch and worm, no change. Also turned it upside down and let it sit for a few hours, pulled it a few more times, put plug back in, exact same. It will pull over slowly if I keep hard constant pressure on it, but if I try to yank it, it's like I get a little and it just stops.

Could it be the oil on the rings from install? I shot a little gas in there and let it sit, should I pour a bunch in and pull it over without the plug in and then try and drain it? I'll admit I've put new seals or P&C in at least a good 15 saws and I very well might have had this happen before but I'm awful forgetful and don't remember! Haha.
 
You may have used too much oil when assembling the saw. I';d tip saw over and pull recoil w/o the plug. Suppose you can use a little mix and do the same thing. Finally when the decomp arrives I'd install it and see how much of a difference it makes I doubt that was the issue however.
 
Take off the recoil and check for function and proper rope length. Then, take out the spark plug and move the engine by turning the flywheel. Check coil gap and make sure the ground wire and screw are seated correctly in the cylinder. Did you plug the decomp? Is the fw seated on the shaft correctly? Decomps are not needed on this series regardless of model.
After all this, put the plug back in and carefully tick it over by the flywheel (don’t jam your fingertips lol). Any binding, weird noises, or resistance not caused by excess oil is bad.
 
I built two Meteor 039's. Both kits needed a little clean up before assembly. Check ring gap (or lack thereof). Check the bolt you use to fill the decomp hole. Inside end should be flush with chamber surface. Adding the second pawl is easy, the starter drum with the 029 was set up for two pawls, just find the right pawl and the two-pawl clip. And do trying flushing out the asembly lube.
 
You may have used too much oil when assembling the saw. I';d tip saw over and pull recoil w/o the plug. Suppose you can use a little mix and do the same thing. Finally when the decomp arrives I'd install it and see how much of a difference it makes I doubt that was the issue however.

I'm kind of leaning toward this and I think I'm going to pour a good amount of gas in there and then tip it upside down and pull it over a bunch without the plug in and see if that cures it. I'll see if I can do that today.



Take off the recoil and check for function and proper rope length. Then, take out the spark plug and move the engine by turning the flywheel. Check coil gap and make sure the ground wire and screw are seated correctly in the cylinder. Did you plug the decomp? Is the fw seated on the shaft correctly? Decomps are not needed on this series regardless of model.
After all this, put the plug back in and carefully tick it over by the flywheel (don’t jam your fingertips lol). Any binding, weird noises, or resistance not caused by excess oil is bad.

I don't think anything is hitting anywhere because like I said it pulls over smooth as butter without the plug in. And I looked at the spark plug and there are no signs of the piston hitting it at all.

With the plug in I can turn the flywheel by hand, and it doesn't seem off at all, just very high compression. Still smooth just hard to turn before the pop which is normal.

I built two Meteor 039's. Both kits needed a little clean up before assembly. Check ring gap (or lack thereof). Check the bolt you use to fill the decomp hole. Inside end should be flush with chamber surface. Adding the second pawl is easy, the starter drum with the 029 was set up for two pawls, just find the right pawl and the two-pawl clip. And do trying flushing out the asembly lube.


That's good to know, I think I'd like to do that for both my starters so they last longer.
 
Well I poured a fair amount of gas in it today, let it sit for a bit. Turned it upside down and pulled on it 20+ times. Plug back in, same thing, starter just seems to want to bind. It feels like the starter itself so I ordered a double pawl kit and we'll see if that does the trick. Do most of the 290 & up saws usually have the two pawls? All the 029/290 & 390 starters I have had only had one pawl.
 
I'm having the same problem with my 390 build. It's a design flaw, Stihl uses a stupidly small pulley in these saws and it makes it very difficult to pull over. The fact my decomp kicks off prematurely doesn't help either.
If anyone knows of a larger pulley that would fit these saws I'm all ears.
 
I'm having the same problem with my 390 build. It's a design flaw, Stihl uses a stupidity small pulley in these saws and it makes it very difficult to pull over. The fact my decomp kicks off prematurely doesn't help either.
If anyone knows of a larger pulley that would fit these saws I'm all ears.

Well good to know I'm not the only one. I've fixed enough pieces of crap apparently to be able to tell fairly well when the starter is binding itself and it sure seems like that is what it's doing.
 
The ms250 has the same issue. It gets more tolerable after break in, I'm hoping the 390 does too. I understand using a large size rope helps somewhat, I assume it fills the pulley better, and the start of the pull has in effect a larger diameter because of the thicker rope when you use them cut to the same length.
 
Well I installed the double pawl kit finally. Still wanted to just bind up it felt like. Pulled the decomp plug out, which was the correct plug btw, put the factory stihl decomp in, away she goes. Once it fired and ran a little I didn't have to do it again or push the decomp in. Runs fine now, pulls fine. Must have just been real tight for that first bit and was somehow making the starter act funny. Thanks for all the suggestions and info everyone.
 
In have built about 50 of these saws and with the pop up piston. I can start them, but have had to add a decompression valve for some of the weaker buyers.
 
Had the same experience with the 390 today. After a couple tanks of gas it's actually tolerable now. Still wished they would have equipped it with a larger pulley though, good thing it starts quick.
 
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